Acting director of Civil Aviation, Chris Ford said the aircraft was found on the seabed, 59 metres below the surface, inverted but largely intact.
"Examination of the aircraft's propellers indicated that they were under little or no power at the time the aircraft impacted the water,'' Mr Ford said.
"The propeller angles were in a position usually associated with a cruise setting.''
He said the operation to find and recover the wreckage from the seabed was "challenging''.
The CAA inquiry into the accident was continuing, and investigators remained open-minded as to the cause or causes, Mr Ford said.
"There is still a lot of work to be done.''
The focus for the safety investigation was to identify lessons that could be learned and applied in order to prevent future accidents, Mr Ford said.
The investigation had not identified any immediate safety related issues or lessons.
The CAA expected its final report into the crash to be released sometime this year.
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The investigation will continue to analyse:
- technical and maintenance history associated with the aircraft;
- Mr Hertz's flying background and experience;
- analysis of Air Traffic Controller voice recording;
- weight and balance calculations;
- flight aerodynamics; and
- regulations relating to foreign aircraft permanently operating in New Zealand.